Influence of pomelo pericarp essential oil on the structural characteristics of gelatin-arrowroot tuber flour-based edible films

Abstract

The present study examined the comprehensive effects of incorporating pomelo pericarp essential oil (PEO) at varying concentrations (0.5, 1.0, 1.5, and 2.0%) into gelatin-arrowroot tuber flour (GEL-ATF) based edible films and evaluated the influence on various structural properties. ATF was prepared from Maranta arundinacea L. tubers using a carefully controlled method to ensure its quality and suitability as a polysaccharide base in film formulations. The results indicated that adding PEO to the GEL-ATF films decreased L, a, and b color values and increased opacity values, especially at higher PEO concentrations. Furthermore, the appearance of both GEL-ATF and GEL-ATF-PEO films exhibited similar characteristics. Incorporating PEO significantly reduced moisture content and water vapor permeability (WVP), indicating enhanced barrier properties against moisture. Additionally, an increase in PEO concentration resulted in decreased film solubility. A decrease in tensile strength (TS) but an increase in elongation at break (EAB) was observed in the GEL-ATF films with higher PEO concentrations (>1% PEO). Slight variations in thermal degradation patterns with increased PEO addition in GEL-ATF were noticed, while X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FTIR) results of the tested films provided insights into structural and chemical modifications, indicating changes in crystallinity and molecular interactions upon increased PEO concentration in the film compositions. The microstructural observations confirmed that PEO incorporation led to smoother film surfaces, suggesting a more uniform matrix, which could enhance the film's barrier and mechanical properties. Furthermore, applying PEO into GLE-ATF films exhibited strong antimicrobial activity against Bacillus cereus ATCC 11778. Overall, the present study found that the higher PEO (>1%) concentrations significantly influenced the physical and mechanical properties of GEL-ATF-based edible films. This newly developed edible film could be an effective alternative to inedible polymers for sustainable food packaging solutions.